In a stunning development, Mayor Bloomberg announced today that the architect of some of the city’s most far-reaching projects was leaving the administration to become president of Bloomberg LP, the mayor’s worldwide information services company.

Dan Doctoroff is stepping down from his post as Deputy Mayor for Economic Development and Rebuilding at the end of the year.

Doctoroff, a wealthy investment banker who was being paid $1 a year, told reporters he had been job hunting for months and was considering several offers before the mayor and Peter Grauer, chairman of Bloomberg LP, approached him last month with an offer to head the firm.

According to Bloomberg, the offer came after Grauer and Doctoroff traveled together to Korea in October and Grauer was impressed by the speech Doctorff had delivered about tourism development.

“Trust me, I did try to convince him to stay,” Bloomberg said of his longtime deputy.

When that didn’t work, Bloomberg said he received approval from the city’s Conflicts-of-Interest Board to make an approach about the Bloomberg LP position.

The mayor praised Doctoroff as “the chief architect of our five-borough economic development plan” and said his impact on the city would be greater than that of the legendary Robert Moses.

Numerous projects and initiatives proposed under Doctoroff remain uncompleted, including the the Hudson River Yards development, the administration’s congestion pricing plan and the sweeping makeover of Willets Point in Queens.